Bit having vertical hammering action



y 1930- J. A. ZUBLIN 1,758,774

BIT HAVING VERTICAL HAMMERING ACTION Filed Aug. 10, 192'? 3 Sheets-Sheet l May 13, 1930. J. A. ZUBLIN I 1,758,774

BIT HAVING VERTICAL HAMMERING ACTION Filed Aug. 10, 1927 s Sheets-Sheet 2 45 TTOF/K/EK J. A. ZUBLIN BIT HAVING VERTICAL HAMMERING ACTION May 13, 1939.

Filed Aug. 10, 1927 3 Sheets-Sheet 3 Patented May 13, 193" PATENT OFFICE UNITED STATES JOHN A. ZUBLIN, F TORBANCE, CALIFORNIA, ASSIGNOB, BY IESNE ASSIGNMENTS,

TO UNIVERSAL ENGINEERING COMPANY, OF LOS ANGELES, CALII'OBNIA, A COB- PORATION OF CALIFORNIA BIT HAVING VERTICAL HAMMERING ACTION Application filed August 10, 1927. SeriaLNo. 211,965.

This invention relates to the rotary system of drilling wells, and it is embodied in a novel rotary bit for use therein.

The ordinary rotary equipment employs a drill pipe having at bit attached-to the end thereof, which drill pipe extends into the well being bored and is rotated by means of a rotary machine located on the floor of a derrick at the surface of the ground. The upper end of the drill pipe is provided with a swivel head to which is connected a travelling block by means of which the drill pipe is supported and fed into the well as the drilling operation proceeds. A flexible hose is connected to the swivel head and to the stand pipe of a high pressure pump, by means of which mud water under high pressure is pumped downward through the drill pipe into the lower end of the well at the bit, for the purpose of removing the cuttings from the bit, for supporting the walls of the well column, and for the purpose of mixing the cuttings thoroughly with the mud water so that they will float therewith to the surface of the ground.

In the rotary system, the cutters or bits employed cut entirely by scraping or attritional action; that is to say, the cutting edges are moved over the surface being cut at substantially right angles to the plane thereof. The principle of operation or the manner of cutting of rotary cutters is substantially the same although there are various forms of rotary bits. When rotary bits arrive at harder .formations, such as hard sand or rock, much difficulty is experienced. The cutting of the bit is very slow and the wear on the cutting edges is excessive. The reason for such'slow cutting and excessive wear reposes in the manner form satisfactorily in hard formations due to these little blows with their sharp teeth. In soft formation, however, roller bits will ball up and make drilling impossible. Soft and sticky formations require the sliding and slicing motion particular to fish tail bits and disc bits.

It is an object of this invention to provide a drilling apparatus which has the combined advantages of the various types of rotary bits and which drills equally well in soft and hard formations.

Another object of this invention is to provide a rotary bit in which the cutter has a combined hammering motion and sliding mot1on. The advantages of the hammering motion in hard formations are proven by the roller type of rotary bit. In my invention, the hammering motion is accentuated and is many times larger than the small blows of the teeth of the roller bits.

A further object of the invention is to pro vide a rotary bit in which the cutter has a steady pressure against the bottom of the hole, this pressure being interrupted periodically by blows which cause the teeth or blades thereof to materially penetrate the formation.

v Other objects and advantages of the invention will be made evident in the. following description Referring to the drawings in which I illustrate a preferred form of the invention,

Fig. 1 is a diagrammatic view illustrating the utility thereof.

Fig. 2 is an elevational view showing the shank of the bit in raised position.

Fig. 3 is a view similar to Fig. 2 showing the shank in lowered position.

Fig. 4 is an enlarged elevational view.

partly sectioned, showing the bit in a position corresponding to Fig. 2.

Fig. 5 is a view similar to Fig. 4, this view showing the bit in a position corresponding to Fig. 3. Y Fig. 6 is a section taken on the line 6-6 of Fig. 4.

Fig. 7 is a section taken on the line 7-7 of Fig. 5.

Fig. 8 is a diagrammatic view ill strat ng the motion of the drill tion of the bit.

Figs. 9 to 13 inclusive are diagrammatic views illustrating the gyrating reciprocatmg motion of the bit.

Referring to Fig. 1, 20 represents the rotary bit embodying the essentials of this invention, this rotary bit being secured to the lower end of-adrill column or drill pipe 21. The drill pipe 21 extends upward through the well 22 and passes through a rotary table 23 of a rotary machine situated on the floor 24 of the derrick, the drill pipe 21 being rotated by the rotary table 23. Connected to the upper end of the drill pipe 21 is a swivel head 25 which is supported by a travelling block 26. Connected to the swivel head 25 by means of a standpipe 27 and a rotary hose 28 is a high pressure pump 29 which draws mud water from a sump 31 and forces pipe during the operait downward through the drill pipe 21 to the bit 20.

Referring particularly to Figs. 4 to 7 inclusive, the bit 20 of my invention has a body 34, which is formed concentric with the axis A-A of the drill pipe 21. The upper end of the body 34 has a threaded pin 35 by means of which the bit 20 is attached to the lower end of the drill pipe 21. An eccentric formation 37 is formed at the lower part of the body 34, this eccentric formation having an inclined pin 38 depending. therefrom. This inclined pin 38 is formed concentric of the axis CC, as illustrated in the drawings. I prefer to provide the inclined pin 38 in the form of an upper part 39 which is integral with the body 34, and a lower part in the form of a bearing member 40. The hear ing member 40 has a threaded projection 41 which screws into a threaded recess of the upper part 39. This bearing member 40 provides an annular thrust bearing face 44 which surrounds the upper end of a cylindrical projection 45, and has a radial bearing face 46 which is provided by the cylindrical projection 45. This cylindrical projection 45 is formed at the extreme lower end of the bearing member 40, as shown.

The body 34 is provided with a mud water passage 48, the lower end of which is connected to a mud water opening 49 of the bearing member 40. A branch opening 53 is'connected between the upper part of the opening 49 and the inner part of the thrust bearing face 44.

The pin 38 is adapted to rotatably carry a cutter 59. This cutter 59 has a cup-shaped portion 60 in which a cavity 61 is formed. The pin'38 is adapted to extend into this cavity 61. There is provided in the cavity 61 a thrust journal face 63' which is adapted to engage the thrust bearing face 44 of the bearing member 40 at certain times during the operation of the bit, as will be pointed out provides a cylindrical radial journal face 64 which is adapted to enga e the radial bearing face 46. The thrust caring face 44 is arranged to take the thrust of the cutter 59 and the shocks of the hammering action, which will be pointed out hereinafter, and the radial bearing face 46 is arranged to centralize the lower end of the cutter 59. The upper end of the cutter 59 is centralized by an upper radial bearing which is illustrated clearly in Figs. 4, 5, and 6. The upper part 39 of the pin 38 is provided with an external annular semi-cylindrical bearing race 66, and the upper part of the cup portion 60 is provided with an internal annular bearing race 67 which surrounds the bearing race 66. As will be noted from Figs. 4 and 5, the outer annular bearing race is wider than the inner bearing race 66. Adapted to operate in these races 66 and 67 are ball bearings 69. It will be seen that the radial bearing construction, just described, will permit the cutter 59 to move on the pin 38 along the axis CC thereof. The ball bearings 69 are inserted in the races through an opening 70 of the cutter 59 which is normally closed by a threaded plug 71. The upper radial bearing, just described, in addition to serving as a centralizing means for the upper end of the cutter 59, serves as a means for locking the cutter onto the pin 38. From an inspection of Figs. 4 and 5, it will be apparent that the cutter 59 cannot be removed from the pin 38 while the ball bearings 69 are in the races 66 and 67. I

Extending from the lower end of the cup portion 60 is a plurality of pilot blades or digging blades 80 which are of radial extension and are preferably four in number. The peculiar construction of these blades is very important to the operation of the bit. Outer faces 81 at the lower ends of the blades 80 are formed concentric to a point D, indicated in Fig. 4. This point D is on the axis 13-13 which is the center line of the hole being dug by the bit 20. The point D is situated at the intersection of the axes BB and C-C. Formed on the cup portion 60 above the blades 80 is a row of reaming blades 84, having spaces 85 between them.

The upper part of the cutter 59 is provided with a pair of diametrically opposed cams 86. These cams 86 are separated from each other by fiat faces 87 of the upper end of the cutter 59. The cams 86 have inclined faces 88, the upper ends of which are connected to riser faces 89. These riser faces 89 extend substantially in planes parallel to the axis C-C. Formed at the lower part of the eccentric formation 37 of the body 34 are followers 90. These followers 90 are diametrically opposed and extend downward parallel to the axis CC to a 85 hereinafter. This cup-shaped portion 60 also point below the lower inclined face of the eccentric formation 37 and engage, at certain times, the cams 86.-

The operation of my bit is extremely difiicult to describe because the cutter 59 has a three dimensional movement which is radically peculiar and there is no terminology which fittingly explains its motion. When the drill pipe 21 is rotated, the body 24 of the bit 20 is rotated in .synchronism therewith. The entire motion of the bit 20 is centralized around the point D thereof, which is the only point in the entire bit which is stationary. This point D is, as stated before, at the intersection of the axes BB and CC; therefore, it will at once be obvious that the bit does not rotate on its own axis AA which is also the axis of the drill pipe 21, but rotates on the axis BB which is drawn vertically through the point D. The body of the bit gyrates around the axis BB, and the point E, which is at the intersection of the axes AA and CC, moves through an orbit 97, as illustrated in Fig. 8, this orbit being concentric to the axis BB.

The motion of the cutter 59 is somewhat dificult to explain and to understand since it is a combination of a gyrating reciprocating, and a hammering motion. The reciprocating motion of the cutter is illustrated in Fig. 5. As the body 34 rotates, the cutter 59 successively reciprocates from the position shown in full lines in this figure into the position shown by dotted lines 99. Each blade therefore reciprocates between a raised position and a lowered position, as illustrated by full and dotted lines in Fig. 5. In Fig. 5, the reciprocating motion of the cutter 59 is illustrated as being wholly in the plane of the paper, but this is not the case since the cutter 59 gyrates as it recipr'ocates so that each blade, as it moves up and down, also moves at right angles to the plane of the drawing.

The gyratin motion of the cutter as it reciproc-ates is ifiustrated in Figs. 9 to 13 inclusive. The gyrating motion of the cutter may be best understood by following the action of the points 83 of the blades 80 which are four in number and are indicated by small circles a. b, c, and d, respectively, in Figs. 9 to 13. The large circles f and g respectively, represent the core 100 produced by the blades 80, this formation being illustrated in Fig. 8. The dots an, y, and 2 represent the bottoms of the depressions formed in the pilot 101 by the blades 80. Referring first to Fig. 9, the blades 80 are shown in the position they 0ccupy in Figs. 4 and 5 of the drawings. The blade (1 which is on the right, is in its lowermost position in the bottom of the depression as. The blades 6 and d are in positions half way between lowered and raised positions.

Blade 0 is in raisedposition which is its highest position. Thepoint H, as indicated in Figs. 9 to 13, is a point on the body 34 which is at all times adjacent to the lowest blade of the cutter. The body of the bit rotates in a direction indicated by the arrows 98 of Figs. 9 to 13. As the body rotates from the position shown in Fig. 9 into the position shown in Fig. 10, the point H moves one-- ing on its downward stroke, and the point d rises'from mid-position into raised position, finishing its upward stroke. The point a moves from lowered position into mid-position starting on its upward stroke. When the point H moves two-thirds of a revolution, as

indicated by the line 102 of Fig. 11, the point 0 is moved from mid-position into lowered po-, sition and into the depression 2. The point at moves from raised position into mid-position starting on the first half of its downward stroke. The point a moves from mid-position into raised position, completing the last half of its up-stroke. The point '6 moves from lowered position into mid-position, completing the first half of its up-stroke. WVhen the point H has completed one revolution, as indicated by the line 103 of Fig. 12, the point 05 moves from mid-position into lower'ed' position and into the depresson w. The point a moves from raised position into mid-position. The point 6 moves from midposition into raised position. The point 0 moves from lowered postion into mid-position. When the point H has revolved one and one-third revolutions and, as indicated by the line I04 of Fig. 13, the point a is lowered from mid-position into lowered position and completes one entire reciprocation which consists of an upstroke and a downstroke. The point 6 moves from raised position into midposition. The point 0 moves from mid-position into raised position. The point d moves from lowered position into mid-position. Each blade. as indicated, a, b, c, and (Z has moved through one complete reciproca- From the description which has preceded it will be obvious that the cutter 59 does not rotate at the same speed that the body 34 rotates. If the bit were rotated without the cutter engaging anything, the body and the cutter would rotate as one. When the cutter is in engagement with the bottom of the well,

it is in a way geared thereto so that the cutter will rotate but onethird of a revolution.

" erned by the number of blades 80. It is imperat-ive to the successful operation of the invention that there be a positive rotation of the body 34 and of the cutter 59, and it is imperative that there be a relative rotation between these two parts. Since there is a relative rotation of the body and the cutter, the followers 90 of the body 34 will ride upward on the inclined face 88 of the cams 86. Since the cutter 59 is in engagement with the bottom of the hole, the body 34 and the drill pipe 21 will be raised at this time. A relative vertical movement between the body 34 and the cutter 59 is possible because of the design of the radial ball bearing construction consisting of the races 66 and 67 and the balls 69. As shown in Fig. 2, the followers 90 will ride upward to the upper parts of the cams 86 and will move beyond the inclined faces 88. At this time, the drill pipe will be released and will fall so that the body 34 of the bit drops from the position shown in Fig. 2 into the position shown in Fig. 3. In Fig. 4, the bit is shown with the body 34 in raised position. When the follower disengages the cams 86, the body 34 drops into the position shown in Fig. 5. At this time the radial thrust bearing face 44 pounds against radialthrust journal 63 of the cutter 59. All of the weight of the drill pipe and all of the force of the blow is taken by these two faces.

. These faces are of sufficient size to stand the sive, the large dots 110 represent the followers 90 and the small dots 111 represent the portions of the cams 86 from which the followers 90 drop. At the starting of the bit, in Fig. 9, the bit is in the positionshown in Fig. 5, the body 34 being in lowered position. The body 34-remains in lowered position until the followers 90 engage the inclined faces 88 of the cams 86. At this time the body 34 is gradually raised until it reaches a raised position, as shown in Figs. 2 and 4. The body 34 does not reach its raised position until it has rotated two-thirds of a revolution, as illustrated in Fig. 11. At this time, the followers 90, as indicated by the large dots 110, drop from the front edges of the cams 86, which are indicated by small dots 111. There will at this time be a hammering action on the cutter, as previously explained.

has again rotated two-thirds of a revolution, as indicated in Fig. 13, the followers, indicated by the large dots 110, drop from the front edges of the cams which are indicated by the small dots 1 11 and there will be another pounding action. It will be seen that for each revolution and one-third of the drill pipe and body 34, there will be two pounding actions of the cutter 59.

The effect of this pounding action of the cutter is that the blade 80, which is in lowermost position, is driven downward and caused to penetrate the bottom of the hole. This will give the cutting blades a good bite so that the bottom of the hole may be dug away.

Duringthis operation of the bit, mud water is supplied thereto by the high pressure pump 29, this mud water passing through the various passages previously pointed out for lubricating the operating parts and being thrust to the bottom of the hole in order to wash away the cuts.

The form of the invention shown, although it includes the essential features, is not the bodied. There are a number of essential features which may be included in different designs. In the first place, it is essential that there be a forced rotation of the body 34 and that there also be a forced rotation of the cutter 59, the designs of these two parts being more or less immaterial. It is further essential that it be a relative rotation between the body and the cutter. Another essential feature is that there be a means for raising the body and the drill column to which it is connected and suddenly releasing it so that the energy stored therein during the raising may be instantaneously applied to the cutter in order to give it a hammering action.

During a cycle of operation of the bit, there are three kinds of pressures applied to the bottom of the hole. The first pressure is the weight of the cutter itself during the free fall of the drill column and body of the bit. The second is the weight of the cutter and the weight of the drill pipe immediately after the body and drill pipe have moved into lowered position. The third is the weight of the cutter and the Weight of the drill pipeand the pressure equal to the energy of the blow at the instant that the drill pipe and body inove into lowered position and engage the cutter. K

There are many advantages accruing from the invention, the most important of which may be briefly enumerated as follows:

In the first place, it will be seen that the constant weight on the cutter is periodically relieved. This will considerably relieve the strains on the, equipment, reducing breakage and buckling of the drill pipe.

The manner in which the bit operates pro- The body 34 continues to rotate and when it only form in which the invention may be emvides the hole with a rough bottom, this being due to the pounding action. A rough bottom is essential to keep the cutting edges sharp and to the most rapid digging of a hole. Where the bottom of a hole is smooth, the tools will glance off the portions which they engage without penetration.

The bit drills equally well in both hard and soft formations for the following reasons:

WVhen in soft formations the hammering effect of the cutter is fully absorbed and the material is removed by the forced rotation of the cutter. In hard formations the reaction to the hammering action or blows will make the blows increasingly more severe with the increasing hardness and resistance of the formation.

Therefore, in harder formations where a more severe blow is needed, a more severe blow will be had.

I claim-as my invention:

1. In combination: a drill column; means for rotating said drill column; a bearin member mounted on the lower end of sai drill column so as to be rotatable on an axis inclined to the axis of said column; a cutter carried at the lower end of said drill column, and rotatable concentric to said inclined axis, said cutter being adapted to be engaged by said bearing member, thus supporting the weight of said drill column; and means for raising said drill column and dropping it so that said bearing member strikes said cutter.

2. In a bit the combination of: cutter means; means for bringing different portions of said cutter means successively into downward cutting relation with the bottom of a hole; and means for intermittently increasing the force with which said cutting means contacts the bottom of said hole.

3. In abit the combination of cutter means means for bringing different portions of said cutter means successively into downward cutting relation with the bottom of a hole; and means for intermittently and suddenly increasing the force with which said cutting means contacts the bottom of said hole.

4. In a bit the combination of: cutter means; means for bringing difierent portions of said cutter means successively into downward cutting relation with the bottom of a hole; and means for intermittently delivering a blow to said cutter means tending to drive said downward cutting portion thereof into the bottom of said well.

5. In a bit the combination of: a body adapted to be rotated in a well on a given axis; cutter means non-axially and rotatably mounted on said body and resting upon the bottom of said well so as to have a gyratory motion when said body rotates; and means for intermittently delivering a blow to said cutter means tending to increase the cutting action thereof.

6.,In a bit the combination of; a body adapted to be rotated in a well on a given axis; cutter means mounted on said body so'as to be rotatable on an axis inclined to said body axis and longitudinally shiftable on said cutter axis relative to said body; and means for shifting said body upwardly relative to said cutter means and intermittently permitting said body to descend to strike a blow upon said cutter means.

7. In a bit the combination of: a body adapted to be rotated about a given axis in a well; a cutter hub carried by said body and rotatable on an axis inclined to the axis of rotation of said body, said hub being shiftable on its axis relative to said body; means for shifting said body upwardly relative to said hub and intermittently permitting said body to descend to strike a blow upon said hub; and a plurality of picks extending downwardly from said cutter hub about a central space, each of said picks being sharpened at its lower end and extending a distance below the position of nearest approach of said axes of rotation so that when said body is r0- tated on its axis, said picks dig on paths extending downwardly and inwardly beneath the bottom surface of the well.

8. In a bit suited for use in well drilling, the combination of: a body adapted to be rotated about a given axis in a well; a cutter carried by said body and rotatable on an axis inting edges formed thereon at a plurality of points about the axis of rotation of said cutter, there being formed a relatively large open space in the bottom of said cutter which is disposed between and extends above said cutting edges, a major portion of said cutting edges being in contact with the bottom of said well at any one time during the rotation of said body; and means for shifting said body upwardly relative to said cutter and intermittently permitting said body to descend to strike a blow against said cutter tending to increase the cutting action thereof.

9. In a bit suited for use in well drilling, the combination of: a body adapted to be rotated about a given axis in a well; a cutter carried by said body and rotatable on an axis inclined to the axis of rotation of said body, said cutter having downwardly disposed cutting edges formed thereon at a plurality of points about the axis of rotation of said cutter, there being formed a relatively large open space in the bottom of said cutter which is disposed between and extends above said cutting edges, a major portion of said cutting edges being in contact with the bottom of saidwell at any one time during the rotation of said body and means for intermittently striking a blow against said cutter tending to increase the cutting action thereof.

10. In a bit suited for use in well drilling, longitudinal axis of the body, and cam memthe combination of: a body adapted to be robers between said cutter and said body.

tat-ed about a given axis in a well; a cutter carried by said body and rotatable on an axis my hand atLos Angeles, California, this 6th In testimony whereof, I have hereunto set inclined to the axis of rotation of said body, day of August, 1927.

said cutter having downwardly disposed cutting edges formed thereon at a plurality of points about the axis of rotation.of said cutter, there being formed a relatively large open space in the bottom of said cutter which is disposed between and extends above said cutting edges, a major portion of said cutting edges being in contact with the bottom of said well at any one time during the rotation of said body; and means for intermittently striking adownward blow against said cutter tending to increase the cutting action thereof.

11. In a drill, the combination with a body adapted to be rotated about a given axis in a well; of a cutter carried by said body and rotatable on an axisinclined to the axis of rotation of said body; said cutter comprising a hub having a plurality of picks extending downwardly therefrom and adapted to be brought successively into effective position by rotation of said cutter about said inclined axis and means for shifting said body upwardly relative to said hub and intermittently permitting said body to descend to strike a blow upon said hub, said means be-- ing arranged to deliver such blows substantially coincident with the effective positions of the respective picks.

12. A drill comprising a body, a cutter rotatably carried thereby, said cutter comprising a plurality of teeth adapted to be successively brought into effective position by rotary movement thereof and means for intermittently delivering a blow to said cutter in timed relation to the movement of said cutter teeth.

13. In combination: a drill column; means for rotating said drill column; a cutter carried by said drill column and adapted to be continuously rotated thereby; and means between said cutter and drill column for intermittently raising and dropping said drill column onto said cutter.

14:. In a rotary drill bit, the combination of a drill column, a cutter rotatably mounted thereon, means for bringing the teeth of said cutter means successively into cutting relation with the bottom of the hole, and coacting cam members between the drill column and the cutter means, intermittently supporting and releasing the weight of the drill stem, and so positioned withrespect to the cutter teeth as to impart a downward blow in timed relation with the cutter teeth.

15. A rotary drill bit, com rising a body, a cutter slidably and rotatabl mounted on said body, and adapted to rotatfe'at an angle to the JOHN A. ZUBLIN. 

